RD/Midas. You people talk like it's actually one or the other.
It's a nice one though. The white/red pattern is desirable. It probably won't look the exact same as it ages, the pattern will vary a bit before it settles as adult coloration, but it's fun to watch.
And yeah, I wouldn't keep it with the Dat. RD/Midas grow pretty damn fast and get pretty damn aggressive upon sexual maturity (about 4-6"). Chances it uses the Dat as a ragdoll when that time comes is high.